Lower Devonian (Lochkovian) Stromatoporoidea from the Coeymans Formation of Central New York

Abstract

Stromatoporoids are found in the Dayville and Deansboro Members of the Coeymans Formation in central New York, where they are common to rare. The most common species present are Habrostroma centrotum (Girty) and H. microporum (Girty). Present in lesser numbers are Parallelostroma foveolatum (Girty), Atopostroma sp. 1, A. sp. 2, Coenostroma cf. C. monticuliferum (Winchell), Coenostroma sp., Habrostroma cf. H. centrotum (Girty), and Coenostelodictyon cf. C. krekovi (Yavorsky). Although previously reported from the Coeymans, Coenostelodictyon jewetti (Girty) was not found. Species identifications were based on traditional qualitative methods, supplemented by statistics. The assemblage bears affinities with Lochkovian faunas in Virginia and the Canadian Arctic.

The stromatoporoidHabrostromain the upper Silurian (uppermost Pridoli)–Lower Devonian (Lochkovian) of North America, and the paleobiogeographic significance ofH.centrotum(Girty, 1895)

“…Typically laminae and coenostromes thinner than galleries high. Microstructure acosmoreticular” (Stock, 1997, p. 545).…”

“…The microstructure of the pillars in Columnostroma is clinoreticular, as is that in the long subcolumns of Syringostroma . Only Habrostroma and what Stock (1997) incorrectly called Coenostroma of the Pridoli-Lochkovian stromatoporoids have acosmoreticular microstructure. “ Coenostroma ” has more robust pachystromes and pachysteles relative to Habrostroma ; both long and short pachysteles are distributed throughout the skeleton of “ Coenostroma ,” whereas the thinner pachysteles in Habrostroma are distributed in laminar zones.…”

“…4.8, 7.1–7.4, 8.4.1991 Habrostroma centrotum ; Stock, p. 905, fig. 5.1–5.7.1997 Habrostroma centrotum ; Stock, p. 545, fig. 4.1, 4.2.2001 Parallelostroma centrotum ; Stearn, p. 22.

Figure 8.Photomicrographs of specimens of Habrostroma centrotum (Girty) from Maine, Bathurst Island, and Ellesmere Island, respectively, none of which has been illustrated previously.

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“…Lower Devonian (Lochkovian) stromatoporoids have been described from several areas of North America, where in many cases they are highly abundant. These include those from New York (Stock, 1991, 1997), Virginia (Stock and Holmes, 1986), and Bathurst Island, Arctic Canada (Stearn, 1990). Additional previously undescribed stromatoporoid faunas are also present in Maine and Ellesmere Island, Arctic Canada.…”

Treatise Online, no. 11, Part E, Revised, Volume 4, Chapter 15A: Techniques of study: Collection, preparation, and analysis of the Paleozoic Stromatoporoidea

“…Stearn (1989) recorded the intraspecific variability of stromatoporoids and related organisms in terms of Simpson's coefficient of variability. The most extensive use of statistics to distinguish between species has been by StoCK and burry-StoCK (StoCK & burry-StoCK, 1998StoCK, 1991StoCK, , 1997) who have applied multivariate procedures to separate species in large collections from the Lower Devonian of New York. They used cluster analysis in an exhaustive study of 103 specimens of Habrostroma to distinguish the two species, H. centrotum and H. consimile, and to rate by canonical correlation analysis which of the skeletal features were most useful in distinguishing them (StoCK & burry-StoCK, 2001).…”